This invention relates to an apparatus and method for conditioning air and more particularly to an apparatus and method for removing respirable aerosols, such as tobacco smoke, from air. Air conditioning includes controlling the temperature humidity, motion and cleanliness of the air.
Tobacco smoke is often a source of great discomfort to non-smokers. While health hazards of smoke are known, in a home office or living space the smoke has the further detrimental effect of causing discoloration of furnishings, fabrics and painted surfaces which may irreparable. In the winter these problems may be aggravated by the fact that good thermal insulation does not permit smoke concentrations to be diluted with fresh air from the outside.
Particles in the size range of about 0.1 to about 2 microns (.mu.m) in diameter, hereinafter called respirable aerosols are preferentially deposited within the lungs when inhaled. An aerosol comprises a suspension of fine solid or liquid particles in a gas. For example, tobacco smoke particles are typically within this range. Unfortunately, particles in this size range are difficult to remove from air using conventional methods. These particles are generally too small for inertial mechanisms, e.g. direct impact filter, to be effective but too large for diffusion, e.g. Brownian movement, to play any significant role in their transport and removal. Sizes above about 2 .mu.m can generally be removed readily from air using conventional methods such as uncharged fiber filters or an electrostatic precipitator having an electric field established between parallel plates between which the air is passed. Sizes below 0.1 .mu.m tend to be exhaled and not to remain within the lung.
Thus it is desirable to have a means and method especially effective for the removal of respirable aerosols, such as tobacco smoke and dust particles from air.
Accordingly, it is an object of the present invention to provide an apparatus and method for removing respirable aerosols from air.
Another object of the present invention is to provide an apparatus and method for removing respirable aerosols from air wherein the apparatus is of small size and inexpensive to fabricate.
A further object of the present invention is to provide an apparatus and method, which are compatible with existing air conditioning systems, for removing respirable aerosols from air.
Still another object of the present invention is to provide an apparatus and method for electrostatically removing aerosols from air.